Biomass Heteroatom Carbon/Cerium Dioxide Composite Nanomaterials Electrode for High-Performance Supercapacitors

Abstract

Carbon materials have been widely used in fabricating supercapacitors. However, their capacitive performance is poor but can be improved by means of heteroatom doping and increasing active sites. Herein, a green and facile strategy is introduced to synthesize a heteroatom carbon/CeO2 nanoparticles complex (HCCN-x, including C, N, O, and Ce elements) using a natural plant, yellow bean sprout, as the carbon source. According to the results, the calcination temperature provides great influence on the electrochemical properties of HCCN-x. In comparison with HCCN-600 and HCCN-700, the HCCN-800 electrode exhibits outstanding performance with the gravimetric capacitance being up to 752 F g–1 and the capacitance retention remaining 97.5% after 10 000 cycles. Besides, the HCCN-800 electrodes are also assembled in the symmetric supercapacitors with the energy density being 25.5 Wh kg–1. Our research opens up a novel avenue for designing of biomass carbon composites in energy conversion and storage utilization.